METHODS: The study included 143 new cases of HIV-1 infection. Viral RNA was extracted from stocked plasma samples and sequenced for the pol and the env regions using the Sanger method. Near-full length sequencing using MiSeq was performed in 3 patients who were suspected to be infected with recombinant HIV-1. Phylogenetic analysis was performed using the neighbor-joining method and Bayesian Markov chain Monte Carlo method.
RESULTS: MSM was the main transmission route in the previous and current studies. However, heterosexual route showed a significant increase in recent years. Phylogenetic analysis documented three taxa; Mongolian B, Korean B, and CRF51_01B, though the former two were also observed in the previous study. CRF51_01B, which originated from Singapore and Malaysia, was confirmed by near-full length sequencing. Although these strains were mainly detected in MSM, they were also found in increasing numbers of heterosexual males and females. Bayesian phylogenetic analysis estimated transmission of CRF51_01B into Mongolia around early 2000s. An extended Bayesian skyline plot showed a rapid increase in the effective population size of Mongolian B cluster around 2004 and that of CRF51_01B cluster around 2011.
CONCLUSIONS: HIV-1 infection might expand to the general population in Mongolia. Our study documented a new cluster of HIV-1 transmission, enhancing our understanding of the epidemiological status of HIV-1 in Mongolia.
Methods: Patients were diagnosed with CHIK fever by a combination of virus isolation, viral RNA amplification, IgM antibody-, IgG antibody-, and/or neutralizing antibody detection. The whole-genome sequences of the CHIKV isolates were determined by next-generation sequencing.
Results: Prior to 2014, the source countries of the imported CHIK fever cases were limited to South and Southeast Asian countries. After 2014, when outbreaks occurred in the Pacific and Caribbean Islands and Latin American countries, there was an increase in the number of imported cases from these regions. A phylogenetic analysis of 14 isolates revealed that four isolates recovered from three patients who returned from Sri Lanka, Malaysia and Angola, belonged to the East/Central/South African genotype, while 10 isolates from 10 patients who returned from Indonesia, the Philippines, Tonga, the Commonwealth of Dominica, Colombia and Cuba, belonged to the Asian genotype.
Conclusion: Through the phylogenetic analysis of the isolates, we could predict the situations of the CHIK fever epidemics in Indonesia, Angola and Cuba. Although Japan has not yet experienced an autochthonous outbreak of CHIK fever, the possibility of the future introduction of CHIKV through an imported case and subsequent local transmission should be considered, especially during the mosquito-active season. The monitoring and reporting of imported cases will be useful to understand the situation of the global epidemic, to increase awareness of and facilitate the diagnosis of CHIK fever, and to identify a future CHIK fever outbreak in Japan.
METHOD: A research-to-policy forum was convened by TDR, the Special Programme for Research and Training in Tropical Diseases, with researchers and representatives from ministries of health, in order to review research findings and discuss their implications for policy and research.
RESULTS: The participants reviewed findings of research supported by TDR and others. Surveillance and early outbreak warning. Systematic reviews and country studies identify the critical characteristics that an alert system should have to document trends reliably and trigger timely responses (i.e., early enough to prevent the epidemic spread of the virus) to dengue outbreaks. A range of variables that, according to the literature, either indicate risk of forthcoming dengue transmission or predict dengue outbreaks were tested and some of them could be successfully applied in an Early Warning and Response System (EWARS). Entomological surveillance and vector management. A summary of the published literature shows that controlling Aedes vectors requires complex interventions and points to the need for more rigorous, standardised study designs, with disease reduction as the primary outcome to be measured. House screening and targeted vector interventions are promising vector management approaches. Sampling vector populations, both for surveillance purposes and evaluation of control activities, is usually conducted in an unsystematic way, limiting the potentials of entomological surveillance for outbreak prediction. Combining outbreak alert and improved approaches of vector management will help to overcome the present uncertainties about major risk groups or areas where outbreak response should be initiated and where resources for vector management should be allocated during the interepidemic period.
CONCLUSIONS: The Forum concluded that the evidence collected can inform policy decisions, but also that important research gaps have yet to be filled.